I think the "tech" aspect is mostly dependent of the design of the garment, and not the material used. Technical, for me at least, implies a design mostly oriented towards usage and functionality instead of ornament like traditional clothes.
I see some natural materials (like leather, wool, down, etc) as the ultimate goal that synthetic material try to achieve/reproduce. Skin is the perfect permeable yet breathable material. Wool and down are still some of the warmest materials we have.
The first raincoats were made of seal/whale intestines and I see this as technical as f***.
Unfortunately sometimes the alterations made to it to allow us to use it as clothing material (I especially think about leather here) alter their properties and make them less appealing from a technical standpoint.
But I see no contradiction in having technical clothing made of natural material, and for me the j40-l is one good exemple, not perfect, but still in the right direction.

Well, supposedly you can get them back but the process seems lengthy and painful..
https://help.cbp.gov/app/answers/detail/a_id/378/~/refund-(drawback)-of-duty-paid-for-imported-goods-if-exporting-or-returning-the